The invention relates to fuel cell systems and, more particularly, to a system and method for enhancement of hydrogen recycle in connection with same.
An objective in operation of fuel cell systems is to achieve a high overall external hydrogen utilization while keeping internal hydrogen utilization, within the anode, at a low level. Typically, this requires hydrogen recycle blowers, or internal cascading of the hydrogen flow. Cascading complicates the cell stack design and makes purging of the system difficult, resulting in the potential for increased cell stack decay.
Hydrogen recycle pumps are noisy, require control systems, use parasite power and have reliability issues.
It is the primary object of the present invention to provide an improved system and method for addressing the above-identified problems.
It is a further object of the present invention to provide a system and method for operating same wherein hydrogen utilization is maintained constant despite different currents in the fuel cell stack.
Other objects and advantages of the present invention will appear hereinbelow.